The present invention relates to disperse azo dyes in which a 2-oxoalkyl ester is linked to the chromophore. Dyes having this structural element are already known and described for example in GB 909843, WO95/20014 and WO05/056690. It has now been found that disperse azo dyes in which the structural element in question is linked to further selected structural elements in a certain manner have excellent properties and provide dyeings having excellent wash fastnesses and very good sublimation fastnesses.